Multi-layer capacitors are used, for example, for preventing or attenuating, respectively, in the case where a direct voltage is supplied to an active circuit component, particularly an integrated circuit, an unwanted leakage of other radio-frequency signals via the direct voltage supply line which would impair the radio-frequency characteristics of the integrated circuit. For this purpose, radio-frequency blocking capacitances are used. To prevent unwanted resonances from the blocking capacitance and line inductances, the connecting paths between these blocking capacitances and the integrated circuit must be short. To achieve short paths, the blocking capacitances are placed as surface-mountable devices (SMD) or bondable components directly next to a semiconductor chip on the surface of a carrier substrate. The additional space requirement and the increased number of bonds needed for the blocking capacitances is disadvantageous.
The arrangement described is disclosed, for example, in JP 02185052 A.
From the printed documents JP 2001196263 A, JP 2003204164 A, DE 198 47 946 A1, JP 2002198655 A and US 2001/0008479 A1, it is known to integrate the radio-frequency blocking capacitances into a multi-layer carrier substrate for the integrated circuit. This releases space on the surface of the carrier substrate for other active components and reduces the number of wire bonds or also flip-chip connections needed on the substrate surface.
A suitable carrier substrate is, for example, the low temperature co-fired ceramics (LTCC) described in US 2001/0008479 A1 since they have numerous thin electrical layers. In principle, parallel plate arrangements for multi-layer capacitors suitable for integration in carrier substrates are adequately well known and described, for example, in DE 100 19 229 A1, U.S. Pat. No. 5,583,359, JP 2002025856 A and JP 11251180 A. The vertical feed lines and connecting lines leading through the electrode plates disadvantageously lead to parasitic inductances in this multi-layer capacitor. In addition, the overall dimensions of the arrangements correspond to not negligible proportions of the wavelength at high frequencies. This leads to unwanted resonances which greatly restrict the operating frequency range towards the top.
Thus, commercially available multi-layer capacitors by means of which capacitance values of 10 to 100 pF can be achieved already have self-resonant frequencies from about 5 GHz.